Zen Browser

Zen Stable Release

New Features

• You now have the option to sync normal tabs across devices along with your Spaces, Folders, and other data. This can be enabled in Settings > Sync > Sync your Spaces across devices.
• You can now share Spaces, folders and split views to other Zen users and non-Zen users via a shareable link. This can be found in the context menu of a Space, folder or split view.

Fixes

• Noticeably improved performance and battery usage while scrolling, and playing videos.
• Other bug fixes and improvements.

Zen Stable Release

Security

• https://www.mozilla.org/en-US/security/advisories/mfsa2026-82/

New Features

• Updated to Freifox 155.0 and 155.0.1
• By using your Mozilla account, you can now sync your Spaces, Folders, Tabs, and much more between devices! This can be enabled in Settings > Sync > Sync your Spaces across devices.
• The chrome UI now has a better look and feel, implementing squircles and other design elements to make it more visually appealing.
• A new on-boarding experience has been added to help new users get started with the browser and its features.
• Creating a new Space is now faster and requires less animation wait time, making the process more efficient.
• Containers can now be reordered in Settings, and the new order is used wherever containers are listed.

Fixes

• Fixed live folders for GitHub issues not working with the new GitHub UI
• Fixed Zen preventing Linux systems from going to sleep after a long browsing session.
• Fixed arrow-key and Page Up/Down scrolling not working on some pages with embedded content from other sites.
• Fixed live audio streams such as internet radio stopping when playing in the background.
• Other bug fixes and improvements.

Changes

• Font size has been increased for the sidebar text, making it easier to read and navigate through tabs and spaces.
• Zen now uses firefox-portal-detection.com instead of detectportal.firefox.com to detect captive portals and check network connectivity, so network allowlists referencing the old domain need updating.
• PDFs smaller than the paper size can now be enlarged to fill the sheet when printing, by setting the scale above 100%.

Zen Stable Release

New Features

• Update Firefox version to 154.0.1

Fixes

• Improved on session store performance, lowering CPU usage spikes and disk usage when storing the session (#14990)
• Fixed duplicate separator on tab context menu (#15031)
• Fixed minimizing PiP window failing to collapse into the sidebar (#14710)
• Fixed slower access to saved passwords and unexpected Primary Password prompts caused by recent changes to password storage.
• Fixed an issue where addresses were failing to autofill on some sites.
• Other bug fixes and improvements.

Zen Stable Release

Security

• https://www.mozilla.org/en-US/security/advisories/mfsa2026-74/

New Features

• Update Firefox version to 154.0
• Local Zen profile backups are now available on macOS in addition to Windows and Linux, and backups can be restored across all three platforms.
• Sites can now be exempted from having their cookies and site data cleared on shutdown without also being exempted from tracking protection and other cookie restrictions.
• The full-page Translations feature now translates content.
• The full-page Translations feature now runs language identification on all page loads, resulting in an improved experience for offering translations to users.
• Performing a hard reload on a page (holding Shift while clicking the Refresh button) now also clears and updates its cached favicons.

Fixes

• Improved battery life on MacOS when using vibrancy effects
• Improved performance of session restore, having spikes of CPU usage every time the session is stored into disk (#14990)
• Fix multiple glance tabs when joining tabs (#14975)
• Improved rendering performance on MacOS and memory leaks when using WebRTC (#9649)
• Fixed an issue on macOS where closing a browser window could leave behind an invisible window that continued to capture mouse clicks over the area where it used to be.
• Fixed an issue on Windows where an auto-hiding taskbar would not appear until the Zen window had been minimized and restored after launch.
• Fixed an issue where the Windows taskbar would appear in front of a full screen Picture-in-Picture window.
• Fixed PDF documents not being scaled correctly in print preview when the Fit to Page Width option is used.
• Other bug fixes and improvements.

Known Issues

• Following recent changes to Zen's password storage, some users may experience slower performance when Zen accesses saved passwords. Users with a Primary Password enabled may also see unexpected password prompts, such as when starting Zen or opening certain content.

Zen Stable Release

New Features

• Update Firefox version to 153.0.4
• Added support for FFmpeg 63

Fixes

• Fixed feature callouts not using native panels (#14912)
• Fixed hang when using the same tab in 2 windows with different containers (#14905)
• Other bug fixes and improvements.

Zen Stable Release

Fixes

• Fixed infinite media players appearing infinitely in the sidebar when a page has multiple media players.
• Other bug fixes and improvements.

Zen Stable Release

Fixes

• Fixed selecting text at the top of a page making the window drag instead of selecting text.
• Other bug fixes and improvements.

Zen Stable Release

New Features

• Updated Firefox to 153.0.3
• You can now filter draft GitHub pull requests in live folders.
• Compact mode now tracks your mouse even after it leaves the window, the sidebar stays open while your cursor lingers near the window's edge and only tucks away once you move further out. This only changed for Windows and MacOS, Linux is still the same as before.
• You can now move the window by dragging empty space in the top part of a webpage, with native snapping and tiling, just like dragging the titlebar. Links, buttons, and other interactive elements still work as usual.
• You can now have multiple media controls in the sidebar, allowing you to control multiple media sources at once.
• Improved startup performance and feeling

Fixes

• Fixes issue setting keybinds with shift + digit or symbol (#9918)
• Fix closing split tab in one window changing focus of other windows (#13761)
• Other bug fixes and improvements.

Zen Stable Release

New Features

• Updated Firefox to 153.0.1

Fixes

• Various performance fixes, RTX Super Resolution not working, and HDR video playback not working on Windows (#14292)
• Fixed extra divider when urlbar has no results (#14717)
• Fix boost applying wrong size override (#14461)
• Fixed crashes/hangs when creating new spaces (#14713)
• Fixed non-tab drags allowing to switch Spaces (#14724)
• Fixed essential tab reordering not working at maximum capacity (#14726)
• Fixed compact sidebar activation at right screen edge (#14409)
• Other bug fixes and improvements.

Zen Stable Release

Security

• https://www.mozilla.org/en-US/security/advisories/mfsa2026-68/

New Features

• Updated Firefox to 153.0
• High Dynamic Range (HDR) video playback is now available on Windows - this feature needs HDR mode enabled for the display in Windows Settings - Display.
• Improved UI for container selection and management
• It is now possible to merge multiple PDFs by dragging a PDF into the PDF sidebar.
• Added support for Apple's system-wide full-screen keyboard command (Globe-F).
• Zen now verifies and displays Qualified Website Authentication Certificates (QWACs) in accordance with eIDAS regulations.
• Added improved support for videos with overlays so users can more easily access video actions from context menus.

Fixes

• Fixed 'Add tab to essentials' context menu item being always disabled (#14616)
• Fixed external links not being routed properly by Space Routing (#14600)
• Fixed boosts size override not persisting (#14461)
• Other bug fixes and improvements.

Zen Stable Release

Fixes

• Fixed essentials promo UI leaving gap on pressing Esc (#14544)
• Fixed localization strings not being translated in some places (#14605)
• Fixed new Spaces not being able to be removed (#14618)
• Fixed split view drag and drop ending up opening new windows (#14619)
• Other bug fixes and improvements.

Zen Stable Release

Security

• https://www.mozilla.org/en-US/security/advisories/mfsa2026-67/

New Features

• Updated to Firefox 152.0.6

Fixes

• Fixed essentials promo UI leaving gap on pressing Esc (#14544)
• Fixed misaligned symbolic space icons in Space options menu on Linux (#14495)
• Fixed Spaces switching when dragging tab to another monitor (#14511)
• Fixed tab order flipping when moving tabs between workspaces (#14495)
• Fixed a hang that could occur after using a file picker dialog on macOS 26
• Other bug fixes and improvements.

Zen Stable Release

New Features

• Updated to Firefox 152.0.5

Fixes

• Fixed some localization strings not being translated in some places (#10749)
• Fixed glance being able to be open a second time when it was already open (#14460)
• Other bug fixes and improvements.

Zen Stable Release

Security

• https://www.mozilla.org/en-US/security/advisories/mfsa2026-62/

New Features

• Updated to Firefox 152.0.4

Fixes

• Fixed overflowing addons not having context menus (#14382)
• Fixed copy, paste, undo, redo, and similar keyboard shortcuts not working inside macOS system dialogs such as the Save and Open panels.
• Other bug fixes and improvements.

Zen Stable Release

New Features

• Updated to Firefox 152.0.2 and 152.0.3
• Added 'Edit pinned tab' context menu item to manually set a pinned tab's URL
• Added 'Add Route for Domain' context menu item to quickly add a tab's domain to the Space Routing settings

Fixes

• Prevent sidebar from flickering when moving a tab (#14131)
• Full-screening while on a glance tab will now expand the glance tab to a normal tab (#11766)
• Fixed space routing tabs opening in background when it should be in foreground (#14183)
• Other minor bug fixes and improvements.

Zen Stable Release

New Features

• Updated to Firefox 152.0.1

Fixes

• Fixed transparency not working after updating to 1.21.2b (#14259)
• Fixed frequent crashes affecting users with Intel Raptor Lake processors
• Fixed an issue on macOS where choosing a PDF option, such as "Save as PDF", from the system print dialog would send the job to your printer instead of saving a file.
• Other minor bug fixes and improvements.

Zen Stable Release

Security

• https://www.mozilla.org/en-US/security/advisories/mfsa2026-57/

New Features

• Updated to Firefox 152.0
• Improved support for more advanced cursor movement commands, including those relating to paragraph boundaries, on macOS.
• On Windows and Linux, you can now copy links via the tab context menu by right-clicking a tab and selecting Share > Copy Link, making it easy to copy a link without switching to the tab first.

Fixes

• Fixed space routing overriding tabs with an explicit container (#14242)
• Fixed background tabs focusing on routed tabs (#14165)
• Fixed opening glance on links while selecting text in links (#8391)
• Other minor bug fixes and improvements

Changes

• Site zooming via keyboard or mouse now offers more zoom levels in smaller increments than before.
• When a PDF or other file that Zen opens directly finishes downloading, it now opens in a background tab if you've switched tabs or closed the original page.

Zen Stable Release

Fixes

• Fixed duplicate bookmarks appearing when re-opening a window in MacOS (#9540)
• Fixed freezes when switching spaces on certain occasions (#14110)
• Improved performance for switching between tabs
• Other minor bug fixes and improvements